This invention relates to a vehicle stabilizer for providing lateral stability to resist overturning forces and more particularly to a self erecting stabilizer which, for example, can be used with dual purpose vehicles which serve for mounting wreckers or cranes and for pulling trailers.
Large wrecker or crane mounted vehicles such as those used for towing trucks or the like must have sufficient lateral stability to resist the forces tending to tip the vehicle when loading. Although a wide body vehicle provides greater lateral stability, the width of the tractor portion of the vehicle is limited by other considerations, not the least of which is the width of the highways upon which they travel. Thus, it is not uncommon to find vehicles of this type provided with some form of lateral stabilizer consisting of support legs positioned outboard of the wheels. These legs are positioned on the ground when the vehicle is loading and act to support the vehicle which may have the wheels thus lifted off the ground.
The construction of the known stabilizers are such that when in the inoperative or storage position they require a relatively large storage space and can interfer with the ground during certain vehicle operations. The available space for storage of the stabilizers is a consideration which can be critical to their use especially on dual purpose vehicles. It is desirable for stability when moving along a highway that the wheels of the vehicle be most widely spaced tranverse to the vehicle chassis. If the stabilizers in the inoperative position remain outboard of the vehicle wheels the effective width of the vehicle is increased and the stabilizers are in a position better served by the wheels.
It is obviously undesirable to position the stabilizer above the tractor bed--the space reserved for the pay load. Furthermore, in vehicles having what is known as a fifth wheel, i.e., the coupling plate on the tractor that couples to the trailer, the available space for locating the stabilizer under the bed, is between the fifth wheel, the tire clearance and the departure angle. This latter angle being the angle between the rear of the rear wheels and the rear of the bed, and it must be greater then the grade any ramp the vehicle will encounter to avoid interference between the tractor and the ramp.
Another consideration in the construction of a stabilizer is its ease of use. Manual deployment of the stabilizer creates operator safety problems especially for vehicles of the larger sizes, and if improperly deployed the stability of the vehicle can be affected.
The known prior art, as evidenced by U.S. Pat. Nos. 3,096,065; 3,107,021; 3,125,352; 3,421,793; 3,450,415; 3,912,289 and 3,053,052, is deficient in one or more of the above considerations, storage and deployment being the main deficiencies.